"This sensor is a very old model that interfaced with our DGX meter. It has been obsolete for several years. Unfortunately this sensor will only work with the DGX meter, not any of our currently offered meters.
I have attached the DGX user manual. The sensor you have is an F150A, and its specs are listed in the beginning of the manual."
The F150A looks to be a fan cooled medium powered sensor with a max wattage of 150W!
Here is the summary of the sensor...
"The F150A-BB-26 is a general purpose fan cooled thermal power/energy laser measurement sensor with a 26mm aperture. It can measure power from 50mW to 150W and energy from 20mJ to 100J. It has the spectrally flat broadband coating and covers the spectral range from 0.19 to 20µm. The sensor comes with a standard 1.5 meter cable for connecting to a meter or PC interface."
Not bad for $29 shipped from eBay. Now to see if it works. At least the fan comes on nicely!